Car aerodynamic in a wind tunnel

Aerodynamics play a crucial role in determining a vehicle's performance, fuel efficiency, and overall design. One way car manufacturers test and improve the aerodynamics of their vehicles is by using a wind tunnel.

In a wind tunnel, a car is placed on a platform and exposed to a controlled airflow, which simulates real-world driving conditions. This controlled environment enables engineers to measure various aerodynamic parameters, including the car's drag coefficient, lift, and downforce.

To maximize the effectiveness of wind tunnel testing, different experimental techniques are employed. Particle Image Velocimetry (PIV) is a particularly powerful tool for studying fluid flow and can provide valuable insights into how air interacts with vehicles.

CFD is a powerful tool that can supplement experimental tests and help maximize the aerodynamic efficiency of a vehicle.
@cfdanalysis.ir

#CFD #EFD #windtunnel #vehicle #aerodynamics #car #engineering #PIV

Determining where fluids such as water and mud, which will splash in the deposits that vehicles enter along the road, will splash under or above the hood is important both for engine health and for not obstructing the driver's view.

In CFD studies, both the identification of moving parts and the capture of jumps in such cases are challenging parts.

@cfdanalysis.ir

#simcenter #cfd #sphflow #siemens

HVAC simulation as input for noise prediction. Modeled as stand-alone HVAC duct in Simcenter STAR-CCM+ and weakly coupled to Simcenter 3D for acoustic propagation
@cfdanalysis.ir

#siemens #simcenter #starccm #acoustic #cfd

I will share some important tips to get high-fidelity CFD simulations.

This simulation is part of my comparative study of motion prediction using a potential flow (PF) solver and Reynolds averaged Navier -Stokes (RANS) for DTMB 5415 in addition to a sensitivity study of setup parameters on the numerical simulation of the motion behavior in quarter waves.

The scope of this research project is to investigate different alternative methods that can be applied to determine ship motions as they differ significantly in terms of accuracy and computational effort.
@cfdanalysis.ir

#projects #cfd #researchanddevelopment #hydrodynamics #offshore #ship #engineering #share #knowledge #design #researchfellow

⁠Our magic number appears to be 0.02 - Why? Help us to find out!

Near stall over wings and airfoils, we often encounter an aerodynamic instability called "buffet" (has nothing to do with food or stocks). For free-transitional cases, an additional instability becomes quite prominent and is associated with an unstable separation bubble. Scaling these frequencies by the maximum reverse velocity as well as length of the separation bubble, we obtain for several test cases at different Mach and Reynolds numbers a constant value of about 0.02. We are still not sure about the exact physical interpretation, which requires more test cases and data. Your turn! ;)

Below a little movie showing on the left pressure fluctuations of an Spectral-Error based Large-Eddy Simulation (SE-LES) of #ONERA's OALT25 profile. On the right-hand-side, we extracted from simulation data dominant oscillations corresponding to the bubble instability, using Spectral Proper Orthogonal Decomposition (#SPOD).
@cfdanalysis.ir


#Transonic #Buffet #Wing #Aerodynamics #CFD #Engineering

I love CFD!

Check out this incredible quadcopter simulation made possible with autonomous meshing and efficient parallel scaling. The iso-surface shows the Q-criterion, colored by velocity.
@cfdanalysis.ir

#cfd #star_ccm_cfd #drones

An Oscillating Water Column (OCW) wave energy converter uses the motion of ocean waves to compress and expand air within a chamber, which drives a turbine to generate electricity. It is a sustainable and environmentally friendly way to harness the power of waves for renewable energy production.

Here's a CFD simulation illustrating that concept. It was modeled in FLOW-3D HYDRO, using two fluids (air & water), coupling motion of the air turbine. You can see the air flow rate and kinetic energy on the graphs, but you could also measure the power output of the turbine.

@cfdanalysis.ir


#waveenergy #cfd #renewableenergy #coastalengineering 🌊

Superposed Rigid Body Motions + Adaptative Mesh Refinement 💡

Star-CCM+ allows to superpose motions which is very useful to define complex motions such as the phase-shifted double rotations shown on the video below. Additionally, local reference frames are automatically created so that you can define plane sections, or any derived parts, that moves with the region. Fixed views can also be set up.

In the example below, the pre-defined VOF criteria of the Adaptative Mesh Refinement (AMR) model was used. It is very easy to set up and allows to put more cells where it matters: around the free surface. For small models such as this one, the AMR can be activated at each time-step, ensuring a very good tracking of the interface.

@cfdanalysis.ir
#cfd #starccm+ #rigidbodymotion #AMR

Airplane CFD - but from the inside!
🌬 This simulation analyzes the air flow inside the passenger cabin of an airliner.
CFD simulations help to maximize passenger comfort in an early design phase.
🦠 The main reason why this simulation was performed: analyze distribution of airborne spread diseases like COVID: https://lnkd.in/em7kxxBG

Physically, this features
💻 a coupled solver,
🕸 polyhedral mesh,
🌀 RANS with k omega turbulence model,
⏲ steady state.
@cfdanalysis.ir
#cfd #simulation #simcenter #airtravel

Siemens Simcenter STAR-CCM+ has pushed a powerful application of #ai into our Simcenter STAR-CCM+ services capabilities for the #automotive industry. Rather than manually selecting, naming, tagging, and processing thousands of parts by hand in a large assembly, a machine learning based feature can do it automatically. This has the potential to reduce what normally would take about a week of dedicated work to being able to be completed in a single day.

Yet another application of #machinelearning for greatly improving the user experience when working with commercial #software. Reach out to engage with our engineering services group on this service if this sounds useful for you.
@cfdanalysis.ir
#cad #siemens #cfd #simulation #simcenter #airtravel

The numerical reproduction of bird flight allows to shed some light on the efficiency-unlocking mechanisms of flapping gaits or flight strategies. Numerical simulation can be exploited in a different way too: it can complement and guide experimental works.

@cfdanalysis.ir

#birdflight #aerodynamics #cfd

This simulation of an electric motor is done in Simcenter STAR-CCM+ and shows some important features:
🧲 electromagnetic simulations, field data first in two dimensions, then mapped to 3D. This GREATLY reduces computational effort.
⚙ motion.
🔥 heat.
💧 flow through the cooling system.

With ease you can optimize electric motors, limiting peak temperatures, ensuring maximum torque and continuous power!
@cfdanalysis.ir
#simulation #simcenter #innovation #starccm #EV #emag

What kind of CFD is this? 🤔
Here we have an application of a transient liquid flow through a trifold membrane. A complex external pressure is applied to the fluid - and the mechanically modeled membrane reacts to that.

Highlights:

♥ Fluid Structure Interaction (FSI)

🖤Overset Mesh

❤ Mechanical Stress



@cfdanalysis.ir

#simulation #simcenter #innovation #cfd

When you ask a fluid mechanic engineer
"how we make babies", the answer can quickly become technical.

@cfdanalysis.ir
#siemens #cfd #baby #starccm #simcenter

⁠'Adding a turbulator will help improve droplet evaporation' - or so I thought. Perhaps that's obvious to some engineering wizards out there, but it wasn't to me. It turns out that the heavier droplets move towards the outside of the helix, coalesce upon impact and actually reduce the overall heat transfer. You can actually see tiny whisps of heated particles as they leave the turbulator. Luckily, Simulations allows you to add layers of physics to explore complex emergent phenomenon instead of relying on engineering intuition. Combined with an impossibly fast NVIDIA GPU-native solver, these simulations can be completed in minutes allowing engineers to rapidly understand the design space. LES turbulence, heat transfer, DEM particles, particle breakup and coalescence, scalar transport, reactions, heat transfer, moving bodies and did I mention heat transfer? And it continues to increase.


@cfdanalysis.ir

#engineering #cfd # #engineers #computationalfluiddynamics #nvidia #hpc #gpucomputing #turbulator #nurbulator

Rocket engine testing Rocket engines enable the generation of thrust, which propels rockets through both atmospheric and space environments. The engine operates by combining fuel and an oxidizer (a source of oxygen) within a combustion chamber. Through the combustion process, hot exhaust gases are produced. These gases are then directed through a nozzle, where the flow is accelerated, resulting in the creation of thrust. In the case of rockets, the working fluid responsible for generating thrust is the hot exhaust produced during the combustion process. This video shows the firing of the SpaceX Raptor engine, which is a cryogenic rocket engine powered by a combination of liquid methane and liquid oxygen. Towards the end of the video, there is a CFD simulation illustrating the plume generated by the engine and the temperatures it can reach during operation.


@cfdanalysis.ir



#engineering #engine #CFD #rocket #testing #space

the performance of a KCS hull equipped with our bio-inspired propulsor. A first validation study showed less than 5% error on
all crucial parameters (e.g. resistance, sinkage, trim, etc.) compared to the Tokyo 2005 and Gothenburg 2010 workshops. Below, the wave pattern of a full-scale model (Re=2.4E9) and the wake formation of the integrated fin (Q-criterion at Q=1.0). In this joint project, the focus is on the evaluation of the stern and bow vertical dynamics at the ship’s designated cruising speed (U=24 kn, Fr=0.26) under calm water conditions. Furthermore, we analyze the potential of added resistance and overall wake alterations caused by the fin motion compared to the ship equipped with a standard B-series propeller. This is especially interesting in large vessel applications, motivating us to explore areas such as wave harvesting, swarm tactics, active kinematic adaptation in real-time, etc.
@cfdanalysis.ir

#CFD #KCS
#Resistance #wave #ship_designing

Siemens Simcenter synergies!
Fluid Structure interaction of a planing hull in waves using Simcenter STAR-CCM+ and Simcenter 3D. Simcenter STAR-CCM+ is used to model the dynamic behavior of the vessel in waves. The impact of the waves result in high pressure forces. These pressure forces are applied on the structural model to investigate the structural safety of the vessel.

@cfdanalysis.ir
#cfd #marine #simulation #cae #siemens

✈️ Aerospace aerodynamics CFD will soon become faster than ever. With the coupled solver becoming GPU-native
in Simcenter STAR-CCM+ 2306 you can run faster, more cost and energy-efficient CFD for aerospace and many more applications. Fasten your seat belts because you are soon ready to take off.

@cfdanalysis.ir


#Simcenter #CFD #AerospaceEngineering

Simulation and experiment of pressure-swirl injector at 1 bar pressure difference.
The simulation was able to correctly predict the shape of the exit spray compared to the experimental work.
This type of spray is called onion-shaped spray, which is created when the pressure is very low.
#CFD
The simulation was also carried out using a volume of fluid model considering two-dimensional axisymmetric swirl conditions.
#EXPERIMENT
Fast imaging was employed based on the backlighting technique to experimentally investigate the behavior of the exit liquid sheet.
High-speed PCO camera (to capture images using an exposure time of 9 μs and Nikon macro lens (100 mm focal length)).
@cfdanalysis.ir
#Pressure#swirl#atomizer #VOF #PCO camera #Backlighting

I love CFD! his propeller surface piercing simulation, showing the formation of water
drops, is just awesome. (Here the mesh is shown on the mid-plane and the iso-surface represents a
void-fraction of 0.5.)
@cfdanalysis.ir


#Marine_cfd #cfd #Propeller#ship_propeller